I'll describe the situation and ask questions at the end:
Tank is my new 65g, has been running for exactly a month. Temp/humidity are consistently 81F/80%. Only the msw pool has a bubbler, which runs for a half hour once every 3 hours during the day. **Edit: forgot to add that I have an LED light rated for planted tanks (mung bean and chia sprouts LOVE it).
The bamboo is a large tube/tunnel, open on both ends with large holes on both long sides, and it is suspended above the msw pool on one short end of the tank. The msw pool is the only one with a bubbler in it, and I typically have overspray onto the glass and all nearby structures/decor. Though the actual spray doesn't reach as high as the tube, the bamboo appears to be suffering water damage. Mold is growing on all the cut edges of the bamboo. I have a cluster of bamboo sticks next to the msw pool but can't tell if it has mold (I'm pulling it out to check).
A large piece of grapevine runs through the middle third of the tank. The parts that are on the sub are actually siliconed to small pieces of plexi, with pebbles and coarse oyster shell siliconed over them (so it's plexi touching the sub). Tiny white fuzz is over maybe 25% of the grapevine, and there appear to be some dark (greenish?) spots as well.
The fishnet hanging over the msw pool is always soaking wet in msw. I think I see some fuzzy spots--which could just be frayed net--I'm going to look at it more closely when I open up the tank to deal with all this later today.
When we were building the tank, all wood was soaked in half strength msw overnight and then dried for several days before going into the tank. The water that is spraying out of the pool is full strength msw.
Questions:
Do you get overspray from your bubblers? Does it cause problems (mold, overly wet sub, etc.)? What can I do to limit the spray (I have a tiny pump with the smallest airstone I could find)? I was actually about to add a splitter and start bubbling my fw pool, but now I'm hesitant in case it's going to cause problems with the cholla and coco hut nearby.
How do I remove the mold from the bamboo and grapevine? Soaking in half-strength msw didn't prevent it, so I'm not inclined to soak again. I've read I can scrub it off with a marine salt paste. Do I need to bake the wood?
How can I prevent this happening again without re-designing my entire tank layout? Or should I just bite the bullet and relocate the bamboo away from the msw (or relocate the pool away from everything else)? The grapevine isn't getting wet, though, and it's also molding. I'm putting a fan in asap (it shipped while I was out of town), but it probably won't cover the entire tank area. Should I point it towards the msw pool?
My 10g and 20g all held 80F/80% without mold ever appearing on anything but day-old fruit, so this is new for me. I even had oak branches for climbing and eating in those tanks for months, but in the new tank a small stick in the leaf litter dish grows mold in a day and a half.
Thanks. 
Good luck!